1910s: The Boston terrier becomes the top dog and remains the only American breed to reach that spot.Dogs
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1920s: The German shepherd takes over at No. 1 in 1925.Inna Felker
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1930s: Boston terriers reclaim the top spot, and cocker spaniels begin their impressive climb. In the 1930s, the decade of the Great Depression, all top 10 breeds are small or medium-sized companion dogs.Tatiana Katsai
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1940s: Cocker spaniels (American and English, all colours) begin their reign. Influences included My Own Brucie, who won dozens of best-of-show titles and a likeness on the cover of Life Magazine.cynoclub
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1950s: The beagle becomes the nation’s top breed for most of the decade. Charles Schultz’s Snoopy makes his first appearance in national newspapers on Oct. 4, 1950.Michael Nagle
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1960s: Poodles take over as No. 1 in 1960 and stay there until 1982.Timothy A. Clary
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1970s: Poodles have the top spot locked up but in a harbinger of things to come, the Labrador retriever makes the top 10 for the first time.Timothy A. Clary
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1980s: Cocker spaniels return to the top.Chris Hondros
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1990s: Labrador retrievers take over and hold tight through at least 2012. Hollywood’s fascination with pocket pups is having an effect, as the decade marks the first appearance of the Yorkshire terrier (pictured), and the Pomeranian returns to the top 10 for the first time since the 1930s.Michael Nagle
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